“Among the various kinds of glass, we may also reckon Obsidian glass... which Obsius discovered in Æthiopia. This stone is of a very dark colour, and sometimes transparent … Many persons use it for jewellery, and I myself have seen solid statues in this material of the late Emperor Augustus...”

- Pliny the Elder, Natural History, 36.67

Obsidian is a silica-rich volcanic glass that is formed when lava cools so rapidly that crystals cannot develop. In the ancient islands of the Aegean Sea, obsidian was a material more plentiful than flint and easier to shape than copper and so it became the material of choice for cutting tools and weapons during the Bronze Age. Sculptors in the Cyclades used obsidian blades like these to carve figures and vessels from marble, such as ‘Kandila’ - of which we have a fine example. Unused obsidian blades and the cores were also a regular feature of burial assemblages in the Early Cycladic period (3200–2000 B.C.). Obsidian’s capacity to produce blades that were sharper than surgical steel made it very valuable, while its lustrous, dark surface later appealed to Roman tastes for luxury objects such as sculpture, vessels, and jewellery.

The primary source in the Aegean was the island of Melos, where two main sites have been identified and mining of obsidian is thought to have begun as early as the Upper Palaeolithic period and lasting until the Early Bronze Age. From there, large quantities were exported throughout the Aegean and into the western Mediterranean, to be worked into fine cores and blades. Access to Melos’ obsidian reserves appears to have been open, and the material could be collected during dedicated expeditions or even incidental visits, such as fishing voyages. It also circulated more broadly through networks of exchange, with evidence for multiple sources being distributed across the region. This system of obsidian exchange constitutes the earliest demonstrable trade network in world history, offering a rare glimpse into the beginnings of commerce and cultural interaction. It suggests that alongside obsidian, other goods, skills, and ideas likely moved across the same channels, shaping the development of early societies.